Do a lot more reading, before contributing, and you'll start to notice patterns and see helpful advice.
Another thing to try is go to www.asksteem.com and do some searches like:
how to choose tags
profile pic
Remember, this is a content system where there are non-stop articles being published on almost anything you can imagine.
They have been plenty of articles posted already on these questions (numerous times, by many different people, with many different perspectives)...
So you have a lot of answers to choose from. Find one that makes the most sense to you, and run with it. :)